Kelly bushing



Nov. 7, 1939. B. BRoNzAN ET Al.

KELLY BUSHING Filed May 23, 1938 2 Sheets-Sheet 1 NOV. 7y 1939. B. BRoNzAN ET Ax.

KELLY BUSHING Filed May 25, 1938 2 Sheets-Sheet 2 Patented Nov. 7, 1939 UNITED STATES PATENT OFFICE 2,179,006 KELLY BUsHING Application May 23, 1938, Serial No. 209,522

10 Claims.

This invention relates to well drilling apparatus and relates more particularly to bushings for use in the rotary tables of well drilling rigs. A general object of this invention is to provide an improved, dependable and eifective drive. bushing or Kelly bushing for use in a rotary table.

In the rotary method of deep Well' drilling a rotary table is provided at the derrick to drive lor rotate the drilling string. A drill stem or kelly of polygonal cross section is provided on the upper end of the 4drilling string and operates in what is known as a Kelly bushing in the rotary table. The engagement of the Kelly bushing with the kelly is such that rotation is transmitted from l5 the rotary table to the kelly and the kelly is capable of vertical movement through the bushing while the rotation transmitting engagement is maintained. The kelly and the Kelly engaging parts of the bushing are subjected to severe wear and as a result slap and play soon develop between the bushing and the kelly. If this condition is not corrected the drive stem or kelly may be irreparably damaged.

Another object of the invention is t provide a Kelly bushing embodying novel means for adjusting its Kelly engaging parts to maintain them in correct engagement with the drill stem or kelly.

Another object of this invention is to provide a Kelly bushing embodying simple, practical and easily operated means for adjusting the several stem or Kelly engaging parts to preserve the correct engagement thereof with the kelly.

Another object of this invention is to provide a Kelly bushing embodying groups or series of rotatable rollers, each series operating to engage a face of the polygonal kelly and separate means for adjusting the series of rollers to maintain a uniform engagement of the rollers with the faces of the kelly and to assure a well distributed transmission of forces, thereby greatly reducing wear and the accompanying play and looseness.

Another object of this invention is to provide a Kelly bushing of the character mentioned in which separate carriers or cages are provided 'to support one or more series of rollers and each (Cl. Z-23) which the adjusting means are positive and serve to maintain their respective cages and rollers in given or set positions until the adjustments are subsequently changed.

j A further object of this invention is to provide an adjustable Kelly bushing in which the Kelly engaging parts may be adjustedquickly and with a minimum of labor.

'I'he various objects and features of our invention will be fully understoodfrom the following detailed description of a typical preferred form' and application of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a side elevation of the improved Kelly bushing provided by this invention engaged about a kelly and seated in a rotary table, illustrating the rotary table in a central vertical section. Fig. 2 is an enlarged fragmentary plan view taken as indicated by line 2 2 on Fig. 1 showing the kellyin cross` section. Fig. 3 is a vertcal detailed sectional view of the Kelly bushing taken as indicated by line 3--3 on Fig. 2. Fig. 4 is a horizontal detailed sectional view taken substantially as indicated by line 4 4 on Fig. 3. Fig. 5 is a rear elevation of one of the cages and its adjusting element removed from the body and Fig. 6 is a top or plan view of the assembly shown in Fig. 5.

The bushing of the present invention is intended primarily for use in the rotary table of a well drilling apparatus to drive or rotate the drilling string. In the following detailed description we will describe the bushing of the invention employed in a typical rotary table to engage or drive a drill stem or kelly of octagonal transverse cross section. It is to be understood that modifications or changes may be made in the bushing of the invention to adapt it for use with other forms of well drilling equipment and that the particular application of the invention illustrated is not to be construed as limiting or restricting the use or scope of the invention.Y

The typical rotary unit illustrated in Figs. 1 and 2 of the drawings includes a rotary table T rotatably supported on a race or support Il) through a suitable bearing II. A driven pinion I2 meshes with ring gear teeth I3 on the under side of the table T to rotate the table. The table T-is provided with a central vertical opening I4 50 and a master bushing B is fitted in the opening I4 to rotate with the table T. The master bushing B has a central vertical opening I5 whose upper portion is polygonal or square in transverse cross section. The portion of the opening I5 imme- 55 diately below its polygonal part is conical or may be said to comprise, generally, a body I6 to y be seated in the opening I5, a plurality of cages I1 in the' body I6 for engaging the kelly K and means I 9 associated with the cages I1 for adjusting them with respect to the kelly K to obtain the correct engagement of the rollers I8 with the kelly.

The bushing body I6 is a tubular structure or member for carrying' the cages I1 and the other parts of the bushing. The body I6 is shaped to seat in the opening I 51 of the master bushing B. The lower part 28 of the body I6 is round in horizontal cross section and is tapered vto fit in the tapered portion of the opening I5.

The adjacent portion of the body I6 is polygonal or square in external configuration to iit the squareportion of the opening I5 whereby the Kelly .bushing rotates with the table T. The upper portion 2| of the body I6 is round or cylindrical in external configuration for the purpose to be hereinafter described. Four equally spaced laterally projecting lugs 22 are,

provided on the exterior of the body I6 immediately below its cylindrical upper portion 2i. The longitudinal opening of the tubular body I'6 is shaped and proportionedto receive the cages I1 and their adjusting elements. The major upper portion of the body opening is polygonal having four main fiat vertical walls 23 disposed at right angles to one another and corner Walls or diagonal walls 24 lying in vertical planes and connecting the adjacent main walls 23. An annular internal or inwardly projecting flange 25 is provided on the bo'dy I6 at the lower ends of its Walls 23 and 24 to support the cages I1.

The cages I1 form supports or carriers for the rollers I8 and are arranged in the tubular body I6 to have their rollers contact the faces F of the kelly K. The cages I1 may be identical and may be integral one-piece members. In the construction illustrated the cages I1 are frame-like members having fiat parallel upper and lower ends 26 and 21, respectively, and iiat parallel opposite sides 28. The lower ends 21 of the cages I1 are adapted to rest on the flange 25 and the upper ends 26 of the cages lie in a plane slightly above the upper end of the bushing body I6. The outer faces of the cages I1 with respect to the central axis of the bushing are of special formation, as will be subsequently described. The inner side of each cage I1 has two angularly related or convergent vertical faces 29. Vertical openings or slots 30 are provided in the cages I1 to hold or receive the rollers I8. In the form of the invention illustrated there are two slots 36 in each cage I1. The slots 30 have their ends spaced from the upper and lower ends 26 and 21 of the cages I1 and extend horizontally through the cages from between their inner and outer sides. The side walls Aof the slots 30 are preferably fiat and substantially parallel and in the construction illustrated extend outwardly at right angles to the adjacent inner faces 29 ofthe cages I1. The inner corners of the cages I1 have angular parts 3i and the parts 3| of the adjacent cages I1 are in nesting or meshing relation as clearly illustrated in Figs. 2 and 4 of the drawings. Itis preferred that the parts 3l of the adjacent cages I1 have substantial clearance whereby the cages may be independently adjusted toward and away from the central vertical axis of the bushing.

The rollers I8 are the kelly engaging Parts of the bushing. The'rollers I8 may be identical and are cylindrical tubular parts with iiat parallel ends. In accordance with the invention there is a plurality or series of vertically spaced Q rollers I8 in each slot 30. The rollers I8 are supported in the slots 30 to rotate about substantially horizontal axes. The means for supporting the rollers .I8 include shafts or pins 32 arranged in openings 33 in the cages I'L.;A The openings 33 intersect the slots 30 and-th pins 32 extend -through the tubular rollers I8 and have their opposite end portions supported in the openings '33. .The rollers I8 are freely rotatable on their respective pins 32. The pins 32 may be secured in their openings 33 in any suitable manner, for example they may be pressed or force-fitted in the openings. The rollers I8 of a set or series are vertically spaced apart to be independently rotatable. The ends of the rollers I8 have suitable working clearance with the flat vertical side walls of the slots 30. In accordance with the invention the rollers I8 project slightly from the inner angular faces 29 of the cages I1 to cooperate with the kelly K. There is a series of rollers I8 foi` engaging each at face F of the polygonal kelly K. This assures an eiective distribution of turing forces throughout the circumference of the kelly. The rollers I8 are preferably of substantial length to have extensive engagement with the faces F of the kelly K.

It is preferred to provide means for lubricating the rotatable rollers I8 so that the engagement of the rollers with the kelly offers a minimum of resistance to vertical movement of the kelly K through the bushing. The'inner ends of the aligned pin supporting openings 33 are in communication. Vertical lubricant ports 35 extend into the cages I1 from their upper ends land intersect the communicating inner end parts of the openings 33 to deliver lubricant to the openings. Longitudinal lubricant ports 36 enter the pin 32 from their inner ends and conduct the lubricant from the openings 33 to lateral ports 31.. The lateral ports 31 in the pins 32 discharge the lubricant into the openings of the tubular rollers I8 to lubricate the rollers. Suitable grease gun fittings 38 are provided at the upper ends of the ports 35 to facilitate the introduction of lubricant under pressure to the lubricant port systems. The grease gun ttings 38 are preferably recessed in the upper ends 26 of the cages I1.

The means I9 for adjusting the cages I1 to obtain the correct contact of the rollers I8 with the kelly K are important features of the invention. The adjusting means I9 are in the nature of wedge means and each includes a gib or wedge element 39 associated with a cage I1. The elements 39 are plate-like membersY arranged between the outer sides of the cages I1 and the opposing walls 23 of the body I6. 'I'he outer sides of the elements 39 are iiat and have sliding or shifting engagement with the body ing along one vertical edge. nach nb 4o' has a diagonal face 4I cooperating with a diagonal tending out through the slots.

body face 24 and each rib has two vertical surfaces 42 disposed at right angles to one another, one surface 42 cooperating with the side -28 of the related or connected cage I1 and the other surface 42 cooperating with a side 28 of an ad# jacent cage l1 and the vertical edge or side of the element 39 on said adjacent cage. The ribs 49 serve to hold the cages I1 and the e1ementsc39 against lateral movement and thus assist in loeating the assembly in the body I 6. The elements 39 are vertically shiftable in the body I6 and are vertically shiftable with respect to their respective cages -I1. It is to be observed that the elements 39 with their ribs V49 form positive means lfor the transmission of torque between the body I6 and the cages I1 and yet allow or.

produce shifting of the cages I1 toward and away from the central vertical axis of the bushing with no possibility of movement of the cages I1 at right angles to the movement just mentioned.

Connections are provided between the shiftable adjusting elements 39 and their respective cages I1 whereby the cages I1 and their adjusting elements may be handled as units. These connections include vertical slots 43 in the adjusting elements 39 and pins or screws 44 threaded in openings in the cages l and ex- The heads of the screws 44 serve to prevent separation of the elements 39 from their cages 'I1. The heads of the screws 44 are preferably recessed in the outer sides of the elements 39.

The adjusting means I9 further include wedge parts on the cages I1 and the adjusting elements 39 whereby .vertical movement of anelement effects lateral adjustment of its respective cage I1. There is preferably a series of) wedge parts 45 on the youter side of each xage I1 and a complementary or cooperating series of wedge parts 46 on the adjacent or connected adjusting element 39. The wedge parts 45 and 46 have at activefaces sloping downwardly and inwardly relative to the central vertical axis of the bushing. The wedge parts 45 preferably extend horizontally across the outer sides of the cages I1 and the wedge parts 46 may extend across the inner faces of the elements 39 from their ribs 49 to their remote longitudinal edges. The outer sides of the adjusting elements 39 normally bear on the body walls 23 and the wedge parts 49 normally cooperate with the wedge parts 45so that the elements 39 serve to support the cages I1 against outward movement and transmit forces between the cages and the body I6. It will be seen that upward movement of the elements 39 relative to the cages I1 eiects inward movement of the cages and that downward movement of the elements 39 with respect to the cages permits outward movement of the cages. The wedge parts 45 and 46 present broad extensive cooperating faces and the series of wedge parts extend between the upper and lower ends of the cages I1 and elements 39 so that the cages are dependably supported and maintained in vertical positions.

'I'he adjusting means I9 further includes screw means for adjusting or shifting the elements 39 vertically to eect the lateral adjustment of the cages I1. A retaining ring 41 isthreaded on the overlying the upper end of the body. A ring 49 is arranged against the upper ends of the cages I1 and is engaged by the flange 48 of the ring 41. The ring 41 acting through the medium of its flange 48 and the ring 49 serves to hold the cages I1 against upward movement. Screws 59 are passed through openings I1 in the ring 49 andare threaded into sockets 52 in the elements 39. The screws 59 are in the nature of cap screws each having a head 53 cooperating with the upper side of the ring 49.V It will be seen that rotation of the screws 59 in one direction feeds or moves the associated adjusting element 39 upwardly 'and that threading of the screws in the other direction allows -the element 39- to lower or settle by gravity. The screws 59 are located so that their heads 53 are adapted to engage the inner peripheral surface of the flange 48. This engagement serves to prevent turning of the screws 59. Notches 54 are provided in the ange 48 and the ring 41 is adapted to be turned to a position where its notches 54 oppose or are aligned with the screwheads 53. With the ring 41 in this position the heads 53 are free to be fturned so that the screws 59 may be rotated or threaded to adjust the cages I1. It is to be observed' that the heads 53 of the adjusting screws 59 are readily accessible at the upper end of the bushing.

It is preferred to provide means for locking or setting the ring 41 in a position where its notches 54 are out of alignment with the screw heads 53 so that the screws are prevented from turning and the adjustment of the cagesl1 is maintained. The retaining ring 41 is split or provided with a lateral slot 55. Outwardly projecting lugs 59 'are' provided on the ring 41 at 'the opposite sides of the slot 55 anda bolt 51 is passed through openings in the lugs 55. Two outwardly projecting ears 89 are provided on the ringD 41 and are located to be above two of the lugs 22 when the notches 54 are out of alignment with the screws 59. Pins or bolts 6I are passed through openings in the aligned lugs 22 and ears 69 to secure the ring 41 against turning. When the bolt 51 is tightened the ring 41 is clamped tightly to the upper portion 2I of the body I6 and when the bolts 6I are arranged in place the ring is positivelyheld against turning.

In the preferred construction the above described ring 4s is .split cr divided into two secand drilling string. The kelly K may be fed vertically through the bushing as it is rotated. The freely rotatable rollersv I8' offer a minimum of resistance to this vertical movement of the kelly K. The cages I1 are normally held in position where their rollers I8 are in correct engagement with the kelly K by the adjusting elements 39. The adjusting elements 39 in turn are held in position by the screws `59 and the flange 48 of the ring 41 serves to prevent loosening or turning of the screws. Accordingly. the

setting or' adjustment of the cages I1 is maintained indennitely. s

When it becomes desirable or necessary to adjust the cages I1 to compensate for wear orto fit the bushing to the kelly K, the bolts 8|V are removed and the bolt 51 is loosened whereupon the ring 41 is turned to a position where its notches 54 are adapted to receive the screw heads 53. In practice the ring I1 may be threaded upwardly to relieve @he downward pressure on the cages transmitted from the ring 41 through the ring 4 9. 'I'he screws 50 may be easily turned to eil'ect vertical movement of the elements 39 and thus produce inward or outward shifting ofthe cages I1y as desired. In adjusting the cages I1 to obtain the correct engagement of the rollers I8 Awith the kelly K it may be found desirable to thread the several screws l) upwardly until the rollers I8 obtain such a rm contact with the kelly K that the kelly is adapted to raise the lnrshlng through this engagement. 'I'he screws 50 may then be backed oil or loosened slightly until the kelly K slides freely through 'the bushing when raised. It is to be observed that the screws 50 may be individually manipulated to obtain `the desired or correct engagement of the rollers I8 of the individual cages I1 with the Kelly faces F. Following the adjustment of the cages I1 the ring 41 is turned to a position where its notches 54 are out of alignment with the screw heads 53 and the bolt 51 is then tightened and bolts 5I are passed through the openings inthe lugs 22. and ears 60 to secure the ring in this position. 'I'he screws 50 are then locked against turning, as

described above, so that the cages I1 are definitely- The cages I1 held in the adiusted positions. may be adjusted from time to time during the use of the bushing to prevent the development of excessive play between the kelly K and the bushing -rollers I8.

1. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, parts in the opening for contacting the stem, shiftable carriers for the said parts, means holding the carriers against vertical movement in the opening and supporting the carriers for substantially horizontal movement toward and away from the stem, and means for shifting the carriers substantially horizontally to positions where their said parts cooperate with the stem to transmit rotation thereto, said means including vertically movable adjusting elements cooperating with the carriers and means for actuating the said elements.

2. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, parts in the opening for contacting the stem, shiftable carriers for the said parts, and means for shifting the carriers to pop v3. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, parts in the opening for contacting the stem, shiftable carriers for the said parts, and means for shifting the carriers to positions where' their said parts cooperate with the stem to transmit rotation thereto, said means including vertically shiftable adjusting elements bearing against the wall ofthe opening, cooperable wedge parts on the carriers and elements. and means for shifting` the said elements.

4. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, parts in the opening for contacting the stem, carriers for the said parts shiftable horizontally in the opening, and means' for adjusting the carriers to have their said parts in correct contact with the drill stem comprising vertically shiftable wedge elements cooperating with the carriers, and means for operating the Wedge elements vertically.

5. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, carriers shiftable in the opening, pluralities of rotatable rollers carried by the carriers to engage the stem, and means for maintaining the rollers in cooperation with the stein comprising a shiftable adjusting elementassociated with each carrier, cooperable tapered parts on the carriers and their associated elements, and means for individually shifting said elements.

6. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, carriers shiftable in the opening, rotatable rollers on the cages for cooperating with the stem to rotate the same, wedge eements for shifting the cages to bring their rollers into correct cooperation with the stem, screws for shifting the wedge elements; and a member on the body normally preventing turning of the screws.

7. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table'and having an opening for passing the stem, carriersshiftable in the opening, rotatable rollers on the cages for cooperating with the stem to rotate the same, wedge elements for shifting the cages to bring their rollers into correct cooperation with the stem, screws for shifting the wedge elements, and a turnable ring on the body normally preventing turning of the screws and turnable to a position where the screws are free to be turned. v

8. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, carriers in the opening, means supporting the` carriers for horizontal movement, an adjusting element shiftably carried by each carrier, rollers on the carriers for cooperating with the stem, cooperable wedge parts on the carriers and their elements, a member holding the carriers in the opening, screws threaded in the elements and reacting against said member to shift the elements whereby the wedge parts act to shift the carriers, and means normall locking the screws against turning.

9. A bushing for a rotary table to drive a drill stem of polygonal cross section comprising a body to be carried by the table and having an opening for passing the stem, carriers in the opening, means supporting the carriers for horizontal movement, an adjusting element shiftably carried by each carrier, rollers on the carriers for cooperating with the stem, cooperable wedge parts on the can'iers and their elements, a member holding the carriers in the opening, screws threaded in the elements and reacting against said member to shift the elements whereby the wedge parts act to shift the carriers, and means normally locking the screws against turning, said means including a ring threaded on the body to hold the member in place and engageable by the screws to preventturning of the same.

10. A bushing for driving a polygonal drill stem comprising a body having an opening for passing the stem, cages in the body opening shiftable toward and away from the central vertical axis of the bushing, Wedge elements bearing between the Walls of the opening and the cages and shiftabe to move the cages, parts carried by the cages for cooperating with the stem to transmit rotation thereto, cooperating surfaces on the wedge elements and cages for the transmission of torque between the body and cages, and means for shifting the wedge elements to adjust the cages.

BLASITO BRONZAN. GLENN D. JOHNSON. 

